What is it good for?
The Krieg specified in the 15th century glosses refers to the section of the Tactical Approach once the bind has been entered through (say) thrusting, and the opponent acts against it. This is followed with the Winden at the blade to "shame them above and below" with the point (or edge).
The first description of the War follows the entry to the Krieg in the Zornhau section of the glosses (refer to Application 5 of the Zornhau) and seems to be a specific exemplar of Winden in practice.
Specifically, starting at the end of Application 5 for the Zornhau:
Application: The Krieg Completed
1) In with the Wrath-hew, as as he parries, drive and Wind the point of your sword above in to the upper opening of his left side.
2) If he then sets the upper stab off, then remain in the Winding with the hilt before your head (ie stay in the upper hanging), and let the point sink down to the lower opening yet on his left side.
3) If he then follows after your sword with the parrying, then search with the point for the lower opening on his right side.
4) If he then follows after your sword further with the parrying, then drive up with your sword on your left side, and hang the point in above to the upper opening on his right side.
The Krieg in this context refers to the phase of the fight in which a bind has been established.